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Adaptive eigen-subspace algorithms for tracking suddenly disappearing sources

IEE PROCEEDINGS-RADAR SONAR AND NAVIGATION 1995年第6期142卷 277-280页

作者： Yang, JF Hung, JH Dept. of Electr. Eng. Nat. Cheng Kung Univ. Tainan Taiwan

Adaptive eigen-subspace algorithms have advantages in tracking nonstationary signal parameters, for example, the directions of arrival in array signal processing. Most adaptive eigenstructure methods can track all moving and suddenly appearing sources. However, an interesting disadvantage of these algorithms is that they fail to track suddenly disappearing sources. As a result of this failure, false peaks will occur in the angular spectrum at the directions where the sources disappear. The authors show this inherent problem of adaptive eigen-subspace algorithms by theoretical derivations and simulation examples.

关键词： tracking systems tracking algorithms eigenstructures

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Cross-product algorithms for source tracking using an EM vector sensor

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 1999年第10期47卷 2863-2867页

作者： Nehorai, A Tichavsky, P Univ Illinois Dept Elect Engn & Comp Sci Chicago IL 60607 USA Acad Sci Czech Republic Inst Informat Theory & Automat CR-18208 Prague Czech Republic

We present an adaptive cross-product algorithm for tracking the direction to a moving source using an electromagnetic vector sensor and analyze its performance. We then propose a multiple forgetting factor variant of ... 详细信息

关键词： array processing tracking algorithms vector sensor

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algorithms and Results of tracking BeiDou Signals During Strong Ionospheric Scintillation Over Ascension Island

Algorithms and Results of Tracking BeiDou Signals During Str...

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International Technical Meeting of the Institute-of-Navigation

作者： Xu, Dongyang Morton, Yu (Jade) Taylor, Steve Miami Univ Dept Elect & Comp Engn Oxford OH 45056 USA

ISBN: (纸本)9781632660800

It is well known that ionospheric plasma irregularities cause GNSS signal amplitude and phase fluctuations, collectively referred to as ionospheric scintillation, which impact GNSS receiver carrier tracking performance. Understanding of the effect of ionospheric scintillation on GNSS signals is essential to the development of robust GNSS receivers during ionosphere disturbances and the effective utilization of GNSS to monitor and study ionosphere space weather phenomena. There have been extensive efforts in recent decades in studying ionospheric scintillation effects on GPS signals. Recent progress in international GNSS is making it possible to obtain ionospheric scintillation data on other satellite signals. Clearly, ionosphere monitoring and space weather studies will greatly benefit from the increased number of all GNSS satellite signals in space. In this paper, we present real ionospheric scintillation observed on BeiDou B 1I signals collected during a March 2013 experimental campaign on Ascension Island (S7.9, W14.4) and the software receiver signal processing algorithm developed to track BeiDou B 1I signals during strong scintillation. The results will be compared with concurrent measurements obtained using a Septentrio PolaRxS receiver. Performance evaluations of the signal processing algorithm using different tracking parameters implemented in the software receiver will also be presented.

关键词： BeiDou Signal Ionospheric Scintillation tracking algorithms

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tracking Vehicles Through Shadows and Occlusions in Wide-Area Aerial Video

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IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS 2014年第1期50卷 429-444页

作者： Aeschliman, Chad Park, Johnny Kak, Avinash C. Purdue Univ W Lafayette IN 47906 USA

We present a new approach for simultaneous tracking and segmentation of multiple targets in low frame rate aerial video. We focus on building an accurate background model that accounts for both global camera motion and moving objects in the scene. We then apply a probabilistic framework for simultaneous tracking and segmentation that incorporates this background model. By using a background model, we are able to track the object through dramatic appearance changes caused by shadows and lighting changes. Furthermore, the incorporation of segmentation into the tracking algorithm reduces the impact of common tracking problems, such as drift and partial occlusion. Results are shown for the Columbus Large Image Format (CLIF) 2007 data set, demonstrating successful tracking under significant occlusions, target appearance changes, and near similar moving objects.

关键词： AERIAL videography PROBABILISTIC automata tracking algorithms BIG data TRAFFIC monitoring

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Optimal adaptive reset control with guaranteed transient and steady state tracking error bounds

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JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS 2017年第14期354卷 5949-5963页

作者： Davanipour, Mehrnoush Khayatian, Alireza Dehghani, Maryam Shiraz Univ Sch Elect & Comp Engn Dept Power & Control Engn Shiraz Iran

In this paper, a solution for improvement of transient performance in adaptive control of nonlinear systems is proposed. An optimal adaptive controller based on a reset mechanism and a prescribed performance bound is devised. The suggested controller has the structure of adaptive backstepping controller in which the estimated parameters are reset to an optimal value. The designed controller ensures both the transient bound and the asymptotical convergence of the states. It is shown that the tracking error satis-fies the prescribed performance bound all the time, besides the speed of the convergence rate is increased by resetting the estimated parameters. The results have been proved through both the analytical and sim-ulation studies. The proposed method is applied to an Augmented Quarter Car Model as a case study. Simulation results verify the established theoretical consequences that the prescribed performance bound based optimal adaptive reset controller can enhance the transient performance of the adaptive controller. (C) 2017 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.

关键词： ADAPTIVE control systems STEADY state conduction tracking algorithms ERROR analysis (Mathematics) STOCHASTIC convergence

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Improvement of mean shift tracking performance using a convex kernel function and extracting motion information

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COMPUTERS & ELECTRICAL ENGINEERING 2012年第6期38卷 1595-1615页

作者： Mazinan, A. H. Amir-Latifi, A. IAU S Tehran Branch Dept Elect Engn Tehran Iran

Color feature is now taken into real consideration as one of the important cues in the area of objects tracking, in image sequences. This feature has attracted considerable attention, in recent years. One of the well-known tools in color feature extraction is to use mean shift (MS) tracking algorithm. The probability of finding the object location in line with this tracking algorithm is somehow desirable, in image sequences, by maximizing the Bhattacharyya coefficient between both objects and corresponding candidate models. Even though the MS tracking algorithm is just known as a popular tool in the field of object tracking, it does not have sufficient merit to be realized in complex environments, i.e., background with object's similar color, sudden light changes, occlusion types and so on. In such a case, the amount of the present coefficient could truly be decreased, during the tracking process, because of the mentioned environmental problems. A convex kernel function in association with the motion information of video sequences is used in this investigation to improve the MS tracking algorithm for the purpose of overcoming the existing problems. The proposed approach is employed to present the MS kernel function, directly. Thus, by using the investigation in its present form, the capability of the MS kernel is increased. Moreover, by using both color feature and motion information, simultaneously, in comparison with single color feature, noises and also uninterested regions can actually be eliminated. Experimental results on data set illustrate that the proposed approach has an optimum performance in real-time object tracking under the severe conditions. (C) 2012 Elsevier Ltd. All rights reserved.

关键词： KERNEL functions DATA mining PERFORMANCE evaluation COLOR tracking algorithms COMPARATIVE studies INFORMATION theory

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A Novel Object tracking Algorithm Based on Compressed Sensing and Entropy of Information

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MATHEMATICAL PROBLEMS IN ENGINEERING 2015年第1期2015卷 1-18页

作者： Ma, Ding Yu, Zhezhou Yu, Jikun Pang, Wei Jilin Univ Coll Software Changchun 130012 Peoples R China Jilin Univ Coll Comp Sci & Technol Changchun 130012 Peoples R China Univ Aberdeen Sch Nat & Comp Sci Aberdeen AB24 3UE Scotland

Object tracking has always been a hot research topic in the field of computer vision;its purpose is to track objects with specific characteristics or representation and estimate the information of objects such as their locations, sizes, and rotation angles in the current frame. Object tracking in complex scenes will usually encounter various sorts of challenges, such as location change, dimension change, illumination change, perception change, and occlusion. This paper proposed a novel object tracking algorithm based on compressed sensing and information entropy to address these challenges. First, objects are characterized by the Haar (Haar-like) and ORB features. Second, the dimensions of computation space of the Haar and ORB features are effectively reduced through compressed sensing. Then the above-mentioned features are fused based on information entropy. Finally, in the particle filter framework, an object location was obtained by selecting candidate object locations in the current frame from the local context neighboring the optimal locations in the last frame. Our extensive experimental results demonstrated that this method was able to effectively address the challenges of perception change, illumination change, and large area occlusion, which made it achieve better performance than existing approaches such as MIL and CT.

关键词： tracking algorithms ENTROPY (Information theory) COMPUTER vision INFORMATION theory FEATURE extraction (Data processing)

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Batch tracking algorithm for multistatic sonars

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IET RADAR SONAR AND NAVIGATION 2012年第8期6卷 746-752页

作者： Ehlers, F. Orlando, D. Ricci, G. Naval Technol & Res WTD 71 Bundeswehr Tech Ctr Ships & Naval Weap D-24148 Kiel Germany Elettron SpA I-00131 Rome Italy Univ Salento Dipartimento Ingn Innovaz I-73100 Lecce Italy

In this study, the authors propose a new tracking algorithm for multistatic sonar systems, where the measurements collected by different sensors are sent to a fusion centre. The proposed algorithm relies on the main idea behind the track-before-detect paradigm, which consists of processing data from several consecutive pings, and estimates target positions by maximising the likelihood function of the available measurements. The authors assume that one manoeuvring target is present within the surveillance area. The preliminary performance assessment, carried out on simulated scenarios, shows that the proposed algorithm has acceptable performance also when the probability of detection per sensor is low (in the order of 0.3) and measurement errors are significant.

关键词： SONAR tracking algorithms GRAPHIC statics PARAMETER estimation ELECTRONIC data processing PERFORMANCE evaluation

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Mesh objective tensile cracking via a local continuum damage model and a crack tracking technique

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COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2006年第1-3期196卷 304-320页

作者： Cervera, M. Chiumenti, M. Tech Univ Catalonia Int Ctr Numer Methods Engn Barcelona 08034 Spain

This paper describes a procedure for the solution of problems involving tensile cracking using the so-called smeared crack approach, that is, standard finite elements with continuous displacement fields and a standard local constitutive model with strain-softening. An isotropic Rankine damage model is considered. The softening modulus is adjusted according to the material fracture energy and the element size. The resulting continuum and discrete mechanical problems are analyzed and the question of predicting correctly the direction of crack propagation is deemed as the main difficulty to be overcome in the discrete problem. It is proposed to use a crack tracking technique to attain the desired stability and convergence properties of the corresponding formulation. Numerical examples show that the resulting procedure is well-posed, stable and remarkably robust;the results obtained do not seem to suffer from spurious mesh-size or mesh-bias dependence. (c) 2006 Elsevier B.V. All rights reserved.

关键词： tensile cracking smeared crack approach strain softening strain localization damage tracking algorithms mesh dependence

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Circular Motion Guidance Law for Coordinated Standoff tracking of a Moving Target

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IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS 2013年第4期49卷 2440-2462页

作者： Yoon, Seungho Park, Sanghyuk Kim, Youdan Seoul Natl Univ Seoul 151742 South Korea Korea Aerosp Univ Dept Aerosp & Mech Engn Goyang City 412791 South Korea

A guidance law is presented to enable a coordinated standoff tracking of a moving target with multiple fixed-wing unmanned aircraft. The standoff tracking guidance law makes multiple aircraft circle around a moving target while maintaining a specific distance from it with a desired circling rate. The stabilization of a spherical pendulum to a conical motion is applied to the aircraft motion to obtain the standoff tracking guidance commands. The acceleration commands are designed to regulate the position and velocity errors using the Lyapunov stability theory and the backstepping technique. The coordinated standoff tracking with multiple aircraft is achieved by applying the proposed guidance law to a leader-follower formation. The only information transmitted from the leader aircraft to the follower aircraft is the phase angle of the leader. In addition an offset circle is proposed to deal with the aircraft speed limit. Tight phase spacing between the neighboring aircraft is accomplished by tracking the reference position and velocity vectors defined on the offset circle. Numerical simulations and flight tests are performed to verify the effectiveness of the proposed method. Multiple aircraft are successfully guided to a circular motion around the moving target while maintaining tight phase spacing to the neighboring aircraft as well as a desired standoff distance to the target.

关键词： CIRCULAR motion tracking algorithms MOVING target indicator radar AIRPLANES LYAPUNOV stability RADAR target recognition

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